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Steel special moment frame connections with shear-yielding haunches can be used for seismic retrofit and for new construction. In this study, shear-yielding haunch connections were investigated through experimental testing and finite element analysis. Three specimens were tested, each with a W1000 × 591 beam and W1000 × 554 column. The cyclically loaded specimens completed cycles at 0.04 rad prior to low-cycle fatigue of the haunch plates. The monotonically loaded specimen reached 0.064 rad drift. The experimental specimens had 10 to 15% post-yield stiffness, and the fuses reached the ultimate material strength prior to tearing. M-factors for the connection were determined to be 4.7 for life safety and 6.3 for collapse prevention. Finite element models were used to quantify force transfer through the connection and to investigate the retrofit-specific detail. The experiments and finite element models confirmed that a relatively simple design procedure produced acceptable designs. • Haunch connections (W1000×591 beam) with shear-yielding fuses demonstrated acceptable rotation capacity (0.04 rad). • M-factors were 4.7 for life safety and 6.3 for collapse prevention. • Finite element models confirmed the force distribution assumed in the design procedure. • Design procedures and a design example are provided. [ABSTRACT FROM AUTHOR]

In many steel buildings, the columns are attached to the foundation through a block-out in the slab-on-grade that is later filled with unreinforced concrete. Engineers typically neglect the block-out concrete in design, effectively treating block-out connections as exposed connections with pinned behavior. Quantifying the flexural strength and stiffness of block-out connections is helpful for determining moment demands on foundations and may lead to more economical connections at the base of steel moment frames. Eight experimental specimens (two-thirds scale) were subjected to lateral loads to investigate the effects of column size, block-out thickness, and load orientation on connection flexural strength and stiffness. The observed flexural strengths were 1.4–2.7 times greater than those calculated neglecting the block-out concrete, because the block-out concrete effectively thickened and expanded the column base plate. A simple method was developed that predicted the flexural strength of the block-out connections to within 10 percent. The effective flexural stiffness at the base of the columns that were tested could be reasonably estimated using a model that combines the theory of beams on elastic foundations with a base rotational spring. [ABSTRACT FROM AUTHOR]

Experimental testing and finite element analysis were used to quantify the inelastic rotation capacity of replaceable shear fuse connections that exceed the current prequalification limits in AISC 358–22. Three experimental specimens with W1000 × 591 beams were tested per the procedures in AISC 341 Chapter K. Fuse plate geometry and the number of fuse plate bolts varied between specimens. All three specimens completed at least one cycle at 0.04 rad, with one specimen completing a cycle at 0.06 rad under the standard AISC special moment frame connection loading protocol. Using extra bolts on the fuse plate to match the bolts at the top flange in one configuration resulted in higher strains in the fuse yielding regions. Finite element models confirmed that about 90% of the moment at the face of the column was transmitted by the horizontal couple at the beam flange levels and that bolt lines should be more centered on the external connection plates. The connections had high post-yield stiffness and had strain hardening factors of up to 1.52. A more transparent procedure for addressing strain hardening in design was developed. • Special moment frame connections with replaceable shear yielding fuses can be used with heavy wide flange beams. • Fuse strain hardening was the same as the ratio of tensile to yield strength from tension coupon testing. • An improved equation for designing fuse plates was derived. • Force transfer at the beam to column connection was quantified using finite element models. [ABSTRACT FROM AUTHOR]

Identification of the Mondo glucose-responsive transcription factors family, including the MondoA and MondoB/ChREBP paralogs, has shed light on the mechanism whereby glucose affects gene transcription. They have clearly emerged, in recent years, as key mediators of glucose sensing by multiple cell types. MondoA and ChREBP have overlapping yet distinct expression profiles, which underlie their downstream targets and separate roles in regulating genes involved in glucose metabolism. MondoA can restrict glucose uptake and influences energy utilization in skeletal muscle, while ChREBP signals energy storage through de novo lipogenesis in liver and white adipose tissue. Because Mondo proteins mediate metabolic adaptations to changing glucose levels, a better understanding of cellular glucose sensing through Mondo proteins will likely uncover new therapeutic opportunities in the context of the imbalanced glucose homeostasis that accompanies metabolic diseases such as type 2 diabetes and cancer. Here, we provide an overview of structural homologies, transcriptional partners as well as the nutrient and hormonal mechanisms underlying Mondo proteins regulation. We next summarize their relative contribution to energy metabolism changes in physiological states and the evolutionary conservation of these pathways. Finally, we discuss their possible targeting in human pathologies. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) acts as a satiety signal and enhances insulin release. This study examined how GLP-1 production from intestinal L-cells is modified by dietary changes. Methods Transgenic mouse models were utilized in which L-cells could be purified by cell specific expression of a yellow fluorescent protein, Venus. Mice were fed on chow or 60% high fat diet (HFD) for 2 or 16 weeks. L-cells were purified by flow cytometry and analysed by microarray and quantitative RT-PCR. Enteroendocrine cell populations were examined by FACS analysis, and GLP-1 secretion was assessed in primary intestinal cultures. Results Two weeks HFD reduced the numbers of GLP-1 positive cells in the colon, and of GIP positive cells in the small intestine. Purified small intestinal L-cells showed major shifts in their gene expression profiles. In mice on HFD for 16 weeks, significant reductions were observed in the expression of L-cell specific genes, including those encoding gut hormones ( Gip , Cck , Sct , Nts ), prohormone processing enzymes ( Pcsk1 , Cpe ), granins ( Chgb , Scg2 ), nutrient sensing machinery ( Slc5a1 , Slc15a1 , Abcc8 , Gpr120 ) and enteroendocrine-specific transcription factors ( Etv1 , Isl1 , Mlxipl , Nkx2.2 and Rfx6 ). A corresponding reduction in the GLP-1 secretory responsiveness to nutrient stimuli was observed in primary small intestinal cultures. Conclusion Mice fed on HFD exhibited reduced expression in L-cells of many L-cell specific genes, suggesting an impairment of enteroendocrine cell function. Our results suggest that a western style diet may detrimentally affect the secretion of gut hormones and normal post-prandial signaling, which could impact on insulin secretion and satiety. [ABSTRACT FROM AUTHOR]

Raingardens are garden beds designed to capture and filter urban stormwater runoff using a permeable soil substrate and plants tolerant of both drought and inundation. The construction of raingardens is actively promoted in many cities, primarily to protect local waterways from the negative impacts of stormwater such as channel erosion and degradation of water quality. To increase the adoption of raingardens by householders, it might be possible to expand raingarden functionality to simultaneously serve as “vegetable raingardens”. Vegetable raingardens would be beneficial in the context of urban agriculture, as they could overcome both space and water scarcity constraints on home vegetable gardening. However, the potential to grow vegetables in raingardens has not been explored and vegetables are significantly different to conventional, hardy raingarden plants. In an 18-month field trial, we assessed vegetable production in purpose-built raingardens. Stormwater was collected from an adjacent rooftop and was applied to the vegetable raingardens through sub-irrigation. One of the vegetable raingardens was lined underneath and the other was unlined, allowing infiltration of excess water to underlying soils. Sub-irrigation was used to limit plant stress and ensure food safety by reducing vegetable contact with potential contaminants present in stormwater. Control gardens were treated with stormwater delivered through overhead spray irrigation, or with potable water delivered by overhead sprays to also examine differences in water source on yield. A range of vegetables were planted including beetroot, onion, spinach, tomato and broad bean. The vegetable raingardens that were tested produced yields generally similar to the control gardens, which represented traditional watering methods for vegetable gardens. The infiltration-type raingarden, sized 7.5% of its catchment area, reduced both the volume and frequency of runoff by >90%. Results indicate that it is possible to both produce adequate yield in raingardens and maintain the function of raingardens in reducing urban runoff, in terms of discharge to waterways. [ABSTRACT FROM AUTHOR]

Abstract: The importance of bioturbation as an agent of soil and geomorphological change is well known but few observations have been made of spatial and temporal variations in bioturbation rates. We quantified variations in surface bioturbation by ants (particularly Aphaenogaster longiceps) and vertebrates in the sandstone terrain of the Blue Mountains, southeast Australia. Following wildfire during the period late 2001–early 2002, we monitored thirty-three 5m2 plots positioned in six different slope units and in two catchments affected by different wildfire severities. Measurements were made seasonally for six years. Overall, mean rates of ant mounding and surface scraping by vertebrates were similar (246±339g m−2 yr−1 and 274±179g m−2 yr−1, respectively). However, rates varied substantially according to slope unit, showing a marked maximum for both ant mounding and total bioturbation on footslopes. Possible reasons for this spatial variation are discussed. A complex response to various soil and ecological factors such as soil texture, soil moisture and vegetation patterns is the most likely explanation. Associated estimates of topsoil (0–30cm depth) turnover times, based on ant mounding rates alone, ranged from 300 to 100,000years for different slope units. In contrast to previous findings, wildfire severity did not seem to affect bioturbation, possibly because of ant survival in deep nests and spatial patchiness of fire severity. There was likewise no clear link between temporal changes in bioturbation and fire severity; high rates in the first two years after wildfire were followed by lower rates for all burn severity types. There was also seasonal variability that was not directly related to rainfall. The results substantiate the importance of bioturbation in modifying soil characteristics and influencing soil erosion, especially following a major disturbance event like wildfire. [Copyright &y& Elsevier]

Abstract: Great morphological differences exist among fruits and vegetables. In this combined experimental and theoretical study, we predict pumpkin shape evolution and maximum size based on their material properties. Using time-lapse photography and measurements collected by volunteer farmers, we show that as pumpkins grow, they morph from spherical to pancake shapes, flattening up to 50% in height-to-width aspect ratio. By compressing whole pumpkins in material-testing machines, we find that the elastic response of the pumpkin is insufficient to account for the large deformations characteristic of large pumpkins. We hypothesize that pumpkin flattening is caused by the weight of the pumpkin retarding its normal growth processes. We test this hypothesis using a mathematical model that assumes plant growth is stimulated in response to a tensile yield stress. We are able to predict pumpkin shapes consistent with those observed. The observed growth plasticity allows the fruit to redistribute internal stresses, thereby growing to extreme sizes without breaking. [Copyright &y& Elsevier]

Summary: Many accounts of cultural factors in armed conflicts are dependent on circumstantial details. Alternative quantitative approaches suffer from confusion of correlation and cause. This paper describes and exemplifies a third approach to the analysis of cultural factors in war—causal process tracing. Six key steps in implementing causal process tracing are outlined and applied to recent episodes of armed conflict in Côte d’Ivoire and Sierra Leone. The virtue of the method lies in establishing a systematic framework for the comparison and evaluation of cultural mechanisms, thus providing an escape from hazards associated with subjective regression. [Copyright &y& Elsevier]

Abstract: Water availability in rainfed coffee agroecosystems is an important factor in determining the production success of the crop. In this study, an estimate of soil water capture and storage was conducted in order to understand the differences of soil water availability among coffee farms or various management intensities, distinguished here by differences in shade cover level. Measurements of effective soil depression storage, leaf litter and soil moisture were taken in each of the sites. These measurements were taken to better understand how different shade coffee systems may gain or lose opportunities to keep water within the system due to contributions of shade. Three sites of varying shade were chosen in the Soconusco region of Chiapas, Mexico. The medium (30–50% cover) shade site was found to be more effective for precipitation capture when compared to the low (10–30% cover) shade site because of a larger value of effective depression storage (t-test, p =0.05) due to increased soil roughness. This conclusion was supported by significantly higher soil moisture measurements in the medium shade site when compared to the low shade site in the dry season (repeated measure GLM, p =0.001). The high shade (60–80% cover) site was found to have a greater slope than the other two sites, yielding smaller effective storage capacities; yet the high shade site was able to retain 15% of the available rainfall during the dry season through surface storage, possibly because of greater leaf litter and other shade contributions. Farmers may consider the use of shade trees within coffee farms as a practical method toward preserving water within the agroecosystem. [Copyright &y& Elsevier]

Abstract: Francesco Melchiorri began his scientific career as a condensed matter physicist. In the early 1970s he developed an interest in far infrared astrophysics and especially in measurements of the cosmic microwave background (CMB) radiation. First at Florence and later at Rome, his group made measurements of the spectrum of the CMB, the dipole and smaller scale anisotropies, and of the Sunyaev Zeldovich effect. At every stage of this process there were remarkable parallels between Francesco’s career at Florence and Rome and the Author’s career at Berkeley. This paper in honor of Francesco Melchiorri will describe some of these parallels, focusing on measurements of the CMB. [Copyright &y& Elsevier]

Abstract: The European Union has recently implemented a system of regulation for the sector based on principles of competition law. The regulatory framework includes 18 markets where Regulatory Authorities should consider imposing ex ante obligations on dominant players. The paper explores the economic methodology being employed in particular to define market boundaries and concludes that the sector is too unstable for this approach to provide predictability and encourage long-term investment. In particular, emerging infrastructures and services can easily be captured while legacy networks remain subject to perpetual regulation. There are significant costs of excessive regulation and alternative approaches may be better. [Copyright &y& Elsevier]

Everglades restoration will alter the hydrology of South Florida, affecting both water depth and salinity levels in the southern fringes of the Everglades, the habitat of the endangered American crocodile (Crocodylus acutus). A key question is what the effects of these hydrologic changes will be on the crocodile population. Reliable predictions of the viability of endangered species under a variety of management scenarios are of vital importance in conservation ecology. Juvenile American crocodiles are thought to be sensitive to high salinity levels, suffering reduced mass, and potentially reduced survivorship and recruitment. This could negatively impact the population recovery. We addressed the management issue of how the crocodile population will respond to alterations in hydrology with a spatially explicit individual-based model. The model is designed to relate water levels, salinities, and dominant vegetation to crocodile distribution, abundance, population growth, individual growth, survival, nesting effort, and nesting success. Our analysis shows that Everglades restoration, through its effects on water flow to estuaries, may benefit crocodile populations if increased freshwater flow reduces the chance that regional salinity levels exceed levels where small individuals lose mass. In addition, we conclude that conservation priority should be placed on reducing anthropogenic sources of mortality on large individuals, such as road mortality. Finally, research should focus on estimates of annual survivorship for large individuals. [Copyright &y& Elsevier]

A digital terrain analysis of the Huron River watershed, using a new spatial analytic procedure, suggests that many areas do not contribute surface runoff directly to the Huron River. These areas are depressions and internally drained valleys of glacial origin. Understanding gained from this analysis should significantly improve the design of lumped-parameter hydrologic models of undulatory glacial terrains. The analysis also shows that man-made drainage features can greatly increase runoff by connecting parts of the watershed that were previously topographically isolated. Consequently, the current use of contemporary subbasin divides is an inaccurate means of calculating surface runoff in southeast Michigan, because of the incorporation of areas that are not directly contributing runoff to the main river system. For example, 63.1 % of the Huron River watershed is unconnected. An example is presented for Mallets Creek, showing how the new procedure can automate definitions of overland flow planes and catchments in a hydrological model. This model is then used to evaluate the sensitivity of runoff to the introduction of storm sewers that change the potential contributing source area. Results suggest that anthropogenic drainage features have doubled the effective size of Mallets Creek watershed. [ABSTRACT FROM AUTHOR]

A review of the literature suggests that large variations in pore-water chemistry exist within soils. The heterogeneity indicates that in soil microchemical environments, the chemistry of pore water evolves independently from one pore to another due to differences in surface area/volume ratios and water residence time. A plug-flow reactor model was developed to examine which size classes of pores contribute the most solute to water draining out of the soil profile, and to explore how temperature might affect a soil’s ability to generate solute. The model is based on the simplification that soil pores can be approximated as a suite of capillaries of varying diameter. The model simulates each size class of pores as a plug-flow reactor with an unique water residence time and surface area.In the model, the pores which drain at the highest water contents have low surface area to water volume ratios and contribute relatively little to the overall solute flux from a soil. The smallest pores that drain at the lowest water contents were found to have the highest surface area to volume ratios and contribute the most solute. The calculations also suggest that activation energy and water viscosity have competing effects on the temperature dependence of weathering. As the temperature increases, the dissolution rate constant increases and smaller pores drain; however, water residence time decreases. This decrease in the water residence time is due to decreasing water viscosity, which can be incorporated into the dissolution rate law for quartz with an activation energy of approximately −15 kJ/mole. Studies that parameterize the temperature dependence of weathering using the Arrhenius approach can account for this effect by reducing the predicted activation energy by an appropriate value. [Copyright &y& Elsevier]

This paper examines the impact of regulatory intervention in the pricing of access to directory information databases across the EU. Disputes over the terms of access have resulted in conflicting outcomes. Pricing solutions include: usage based pricing; a cost partition according to the number of records taken; pricing by the volume of sales to end-users; or simply free access to the database. The paper argues first, that databases have the essential characteristics of public goods which precludes unfettered competition in their provision. Secondly, there is no pricing solution which will simultaneously achieve economic efficiency, stimulate downstream competition, maintain reasonable intellectual property rights, and cover the costs of the provider of the database itself. Trade-offs therefore need to be made. [Copyright &y& Elsevier]

This study estimates the economic cost of reducing the take of sea turtles in the U.S. Northwest Atlantic Commercial Pelagic Longline Fishery. Sea turtles are protected under the Endangered Species Act. The analysis uses an output-oriented stochastic distance frontier method and draws from a highly unbalanced trip-level panel dataset that had 60 unique vessels that fished between 2006 and 2016. Our results show that mitigating the take of sea turtles is costly. On average, the cost of reducing the take of one sea turtle (or shadow price) equals $36,957. Shadow prices show significant temporal variability and vary by the targeting behavior of the fleets (i.e., tuna vs. swordfish trips). We also find that the technical efficiency of the fishing fleets varies by its targeting behavior. We conclude discussing bycatch management insights from our research. [ABSTRACT FROM AUTHOR]

Special moment frames (SMFs) with replaceable shear fuse (RSF) connections are being used as an alternative to SMFs that form beam plastic hinges. Capacity design of SMFs requires that the maximum moment that can develop at the column face be determined. Experimental work was performed to determine a cyclic hardening factor that can be used to calculate the maximum moment at the column face in SMFs with RSF connections. Five full-scale one-sided moment connections were tested to provide additional data. Data from these experiments were combined with data from previously-reported experiments to evaluate cyclic hardening. The combined data showed that cyclic hardening for RSF connections was greater than for traditional connections because the shear fuses do not experience local buckling. A cyclic hardening factor of 1.42 was shown to be reasonable for RSF design. In computing the maximum moment at the column face, the cyclic hardening factor should be applied to the fuse contribution but not to the elastic moments transmitted by the other connection plates. [Display omitted] • Replaceable shear fuse (RSF) connections prevent beam yielding in moment frames. • Full-scale experiments were performed to quantify RSF connection performance. • Experimental data were used to quantify a strain hardening factor for design. • A design method for computing the expected moment is presented and validated. [ABSTRACT FROM AUTHOR]

The gut-brain axis, which mediates bidirectional communication between the gastrointestinal system and central nervous system (CNS), plays a fundamental role in multiple areas of physiology including regulating appetite, metabolism, and gastrointestinal function. The biology of the gut-brain axis is central to the efficacy of glucagon-like peptide-1 (GLP-1)-based therapies, which are now leading treatments for type 2 diabetes (T2DM) and obesity. This success and research to suggest a much broader role of gut-brain circuits in physiology and disease has led to increasing interest in targeting such circuits to discover new therapeutics. However, our current knowledge of this biology is limited, largely because the scientific tools have not been available to enable a detailed mechanistic understanding of gut-brain communication. In this review, we provide an overview of the current understanding of how sensory information from the gastrointestinal system is communicated to the central nervous system, with an emphasis on circuits involved in regulating feeding and metabolism. We then describe how recent technologies are enabling a better understanding of this system at a molecular level and how this information is leading to novel insights into gut-brain communication. We also discuss current therapeutic approaches that leverage the gut-brain axis to treat diabetes, obesity, and related disorders and describe potential novel approaches that have been enabled by recent advances in the field. The gut-brain axis is intimately involved in regulating glucose homeostasis and appetite, and this system plays a key role in mediating the efficacy of therapeutics that have had a major impact on treating T2DM and obesity. Research into the gut-brain axis has historically largely focused on studying individual components in this system, but new technologies are now enabling a better understanding of how signals from these components are orchestrated to regulate metabolism. While this work reveals a complexity of signaling even greater than previously appreciated, new insights are already being leveraged to explore fundamentally new approaches to treating metabolic diseases. • The gut-brain axis plays an essential role in regulating metabolism and leading therapeutics for T2DM and obesity harness this machinery. • Multiple components of the gut-brain axis are involved in an integrated response to sensory information to maintain whole-body homeostasis. • A systems biology approach utilizing advanced technologies is enabling a detailed mechanistic understanding of gut-brain communication. • This understanding is leading to new approaches that may result in the next generation of therapeutics for metabolic diseases. [ABSTRACT FROM AUTHOR]

Objectives: Approximately 20% of UK women aged 70+ with early breast cancer receive primary endocrine therapy (PET) instead of surgery. PET reduces surgical morbidity but with some survival decrement. To complement and utilize a treatment dependent prognostic model, we investigated the cost-effectiveness of surgery plus adjuvant therapies versus PET for women with varying health and fitness, identifying subgroups for which each treatment is cost-effective.Methods: Survival outcomes from a statistical model, and published data on recurrence, were combined with data from a large, multicenter, prospective cohort study of over 3400 UK women aged 70+ with early breast cancer and median 52-month follow-up, to populate a probabilistic economic model. This model evaluated the cost-effectiveness of surgery plus adjuvant therapies relative to PET for 24 illustrative subgroups: Age {70, 80, 90} × Nodal status {FALSE (F), TRUE (T)} × Comorbidity score {0, 1, 2, 3+}.Results: For a 70-year-old with no lymph node involvement and no comorbidities (70, F, 0), surgery plus adjuvant therapies was cheaper and more effective than PET. For other subgroups, surgery plus adjuvant therapies was more effective but more expensive. Surgery plus adjuvant therapies was not cost-effective for 4 of the 24 subgroups: (90, F, 2), (90, F, 3), (90, T, 2), (90, T, 3).Conclusion: From a UK perspective, surgery plus adjuvant therapies is clinically effective and cost-effective for most women aged 70+ with early breast cancer. Cost-effectiveness reduces with age and comorbidities, and for women over 90 with multiple comorbidities, there is little cost benefit and a negative impact on quality of life. [ABSTRACT FROM AUTHOR]

Prospective data are needed to ascertain the impact of iron chelation therapy in patients with myelodysplastic syndromes. The present 5-year prospective registry analysis was conducted to compare clinical outcomes between chelated and nonchelated patients with lower-risk myelodysplastic syndromes and transfusional iron overload. In an interim analysis at 24 months, we previously reported that chelation therapy was associated with longer median overall survival and a tendency toward longer leukemia-free survival and fewer cardiac events. In the present report, we detail findings from the final analysis at 5 years. We confirm, at the conclusion of this 5-year, prospective, non-interventional study, that overall survival was significantly longer in patients who received iron chelation therapy vs those who did not. Causes of death in the overall population were predominantly myelodysplastic syndromes/acute myeloid leukemia followed by cardiac disease. Time to progression to acute myeloid leukemia was also significantly longer in patients receiving chelation therapy, and significantly fewer patients progressed to leukemia vs those not receiving chelation therapy. Limitations of the study include a potential for clinical bias, as patients with longer predicted survival may have been chosen for chelation therapy, the differences present in concomitant conditions at baseline, and the possibility that some high-risk patients were not identified due to limited cytogenetic classification. [ABSTRACT FROM AUTHOR]

Despite an expanding literature on Ebola-response, few studies detail or reflect on the responses of diverse systems of care. Little is known about how, why or in what ways, strategies of ill-health management were enacted locally, how health-systems power, authority and hierarchy were perceived and contested, or how other social systems, institutions and relationships shaped the response. This paper presents an interdisciplinary analysis of local responses in two early affected districts in Sierra Leone. Drawing on anthropological theories of social ordering and assemblage, we present an analysis of contrasting infection chains in three extended case studies from Bo and Moyamba districts. In contrast to previous scholarship which has understood local actions as being reactive (supporting or obstructing) to a national Ebola response, we show that local arrangements lead and shape responses. Our cases show how multiple, entangled, dynamic and co-existing systems of care influence these responses. Some individuals and communities collaborated with health authorities on measures like reporting and quarantine, others actively opposed them, or played an intermediary role. Collectively, formal health systems actors, local authorities and ordinary citizens negotiated and enacted new arrangements. These arrangements involved compromise and sometimes power was reconfigured. They were also shaped by wider political and historical contexts and by availability or absence of formal healthcare resources. Our research shows the critical importance of understanding how institutions and people involved in healthcare enact diverse "systems of care" and thereby shape Ebola response. Most importantly, our work underlines the need for alignment between formal health-systems and wider social, cultural, political and economic forms of organisation at family and community levels to improve crisis-response and promote sustainable care. In particular, health systems responders need to identify and engage with key brokers – or arrangers – in frontline care systems, with whom mutually acceptable, and effective, reconfigurations of care can be achieved. • Multiple, dynamic, co-existing systems of care shaped Sierra Leone's Ebola response. • Political/historic context, resources, conflict and compromise all shaped care systems. • Diverse local actors negotiated relationships to reconfigure healthcare arrangements. • It is local arrangements that lead and shape crisis-response at the decentralised level. • Health systems need to engage with "arrangers" to reconfigure locally responsive care. [ABSTRACT FROM AUTHOR]

Global debates about vaccines as a key element of pandemic response and future preparedness in the era of Covid-19 currently focus on questions of supply, with attention to global injustice in vaccine distribution and African countries as rightful beneficiaries of international de-regulation and financing initiatives such as COVAX. At the same time, vaccine demand and uptake are seen to be threatened by hesitancy, often attributed to an increasingly globalised anti-vaxx movement and its propagation of misinformation and conspiracy, now reaching African populations through a social media 'infodemic'. Underplayed in these debates are the socio-political contexts through which vaccine technologies enter and are interpreted within African settings, and the crucial intersections between supply and demand. We explore these through a 'vaccine anxieties' framework attending to both desires for and worries about vaccines, as shaped by bodily, societal and wider political understandings and experiences. This provides an analytical lens to organise and interpret ethnographic and narrative accounts in local and national settings in Uganda and Sierra Leone, and their (dis)connections with global debates and geopolitics. In considering the socially-embedded reasons why people want or do not want Covid-19 vaccines, and how this intersects with the dynamics of vaccine supply, access and distribution in rapidly-unfolding epidemic situations, we bring new, expanded insights into debates about vaccine confidence and vaccine preparedness. • Discourses of vaccine hesitancy misrepresent African publics as ignorant or confused. • Covid-19 vaccine anxieties make sense given disease, social and political experiences. • Vaccine supply inequities interplay with uptake in dynamics across scales. • Growing familiarity with Covid-19 vaccines has eroded worries, but not linearly. • Vaccine preparedness must address health system structures and politics. [ABSTRACT FROM AUTHOR]

Abstract: Although there has been increasing research on the adoption of agroforestry technologies over the last decade, few such studies have assessed uptake over a long period and many are based on a single snapshot in time. Furthermore, most of these studies have mainly looked at non-adopters and adopters: only recently have social scientists considered testers. A further category of users neglected in adoption studies has been re-adopters of technologies. Studying this group provides an interesting and more nuanced understanding of adoption and re-adoption. Methodologically, most adoption studies use quantitative methods and fail to link their findings to wider socio-economic, political and institutional settings. This paper presents a study of the dynamics of improved tree fallow use by farmers in Siaya and Vihiga districts of western Kenya over a period of eight years. It uses both qualitative and quantitative data to critically discuss the motivations of adopters, testers/rejecters and re-adopters. The results show that the process of adoption is highly dynamic and variable with farmers planting improved fallows and discontinuing or re-adopting them due to a whole range of factors, of which soil fertility improvement is just one. These factors included incentives from projects, the tying of adoption to credit programmes, prestige, participation in seminars/tours and the availability of a seed market from projects promoting improved fallows. Farmers planting improved fallows for such reasons may be termed ‘pseudo-adopters’. There were significant differences in adoption between the two districts, with more farmers in Siaya planting improved fallows than in Vihiga. A majority of farmers in Vihiga (53%) who were given seed never planted improved fallows, even though they had been exposed to the technology. Some 40% of farmers in Siaya and 38% in Vihiga planted improved fallows but later rejected them. This has some important implications for research and development. For improved fallow technologies to be attractive to farmers, they must provide other tangible economic benefits besides soil fertility improvement. This presents a challenge to researchers who must better attune themselves to the needs and demands of farmers if they wish to see their research findings widely adopted. [Copyright &y& Elsevier]